ABSTRACT
Objective@#To investigate the frequency of KRAS mutation in mucinous epithelial lesions of the endometrium, and analyze the correlation between KRAS mutation and the clinicopathologic features.@*Methods@#The cohort included forty-three cases of mucinous epithelial lesions of the endometrium selected from July 2015 to October 2017 from Beijing Obstetrics and Gynecology Hospital, and 22 control cases. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue sections. Polymerase chain reaction amplification for KRAS exons 2 and 3 was performed, followed by sequencing using capillary electrophoresis. The Fisher exact test was used to compare the prevalence of KRAS mutation among the different groups.@*Results@#The patients′age ranged from 33 to 77 years [mean (55.12±9.34) years, median 55 years]. None of the eight cases of endometrial hyperplasia with mucinous differentiation without atypia showed KRAS mutation. The frequency of KRAS mutations was 1/10 in endometrial atypical hyperplasia, 1/12 in endometrioid carcinoma, 4/11 in endometrial atypical hyperplasia with mucinous differentiation (EAHMD), 6/15 in endometrioid carcinoma with mucinous differentiation (ECMD) and 8/9 in mucinous carcinoma (MC), respectively. The differences were statistically significant between MC versus EC (P<0.01) and MC versus ECMD (P<0.05).@*Conclusion@#The high frequency of KRAS mutation in EAHMD, ECMD and MC indicates that KRAS mutational activation is implicated in the pathogenesis of endometrial mucinous carcinoma.
ABSTRACT
Objective@#To investigate the value of short tandem repeat (STR) genotyping in the diagnostic workup of molar and non-molar gestations with correlation of histological characteristics.@*Methods@#Six hundred and fifty-six cases were selected based on clinically suspected hydropic abortion and/or molar pregnancy from July 2015 to September 2017 at Beijing Obstetrics and Gynecology Hospital. DNA was extracted from dissected chorionic villi and paired maternal endometrial FFPE tissue samples by Simplex OUP™ FFPE DNA Tissue Kit. STR genotyping was performed by PowerPlex 16 HS system.@*Results@#DNA genotyping was informative in 649 of 656 cases, leading to identification of 215 hydatidiform mole gestations and 434 non-molar gestations. Most of non-molar gestations (375 cases, 86.4%) were diploid hydropic abortion. Various trisomy syndromes were found (53 cases, 12.2%), including trisomy 2, 3, 4, 7, 8, 13, 16 and 21. Only 2(0.5%) digynic triploid gestations were detected. Moreover, 4 cases (0.9%) of uniparental disomies (homologous or heterologous) were found. There were 196 cases with histologic diagnostic suspicious of hydatidiform moles were accurate sub-classified. Among them, 59 cases hydatidiform moles were under-diagnosed as diploid hydropic abortions, and 28 cases diploid hydropic abortions were over-diagnosed as hydatidiform moles.Compared with partial moles(PHM), there were no specific histomorphological features between the various types of non-molar gestations and partial moles for definitive diagnostic separation. There was no significant difference in the expression of p57kip2 among PHM, trisomy and diploid hydropic abortions group (P=0.247).@*Conclusions@#STR genotyping can distinguish non-molar gestations from early hydatidiform moles, and efficiently avoid misdiagnosis based only on histological evaluation. Therefore, using STR genotyping, not only can the overdiagnosis of non-molar pregnancy be avoided, but also individualized management can be offered to patients including monitoring of serum hCG.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the clinical utility of short tandem repeats(STR) genotyping technique for diagnosis of partial hydatidiform moles (PHM).</p><p><b>METHODS</b>Ten cases with the original diagnosis of PHM and six cases diagnosed as "favour PHM" or "abnormal villous, PHM not excluded" were selected for the study. The clinical information and follow-up data were reviewed. Histopathologic features were evaluated along with p57 immunohistochemistry. After DNA extraction from each sample, genotyping was performed by AmpFlSTR(®) Identifiler™ PCR kit to amplify 15 STR polymorphism loci plus the amelogenin gender-determining in a single robust PCR.</p><p><b>RESULTS</b>The age of patients ranged from 18 to 49 years (mean=29 years, median=29 years). Two villous populations (7/16), irregular villous contour (13/16), at least moderate trophoblastic hyperplasia (2/16), cistern formation (8/16), syncytiotrophoblastic knuckles (14/16), trophoblastic pseudoinclusions (6/16) and nucleated fetal red blood cells (8/16) were presented in these cases. Of the cases in the study, STR genotyping identified 4 monospermic complete hydatidiform moles (MCM), 3 dispermic partial hydatidiform moles (DPM) and 9 hydropic abortions (HA). The misdiagnosis rate was 13/16 only relied on morphology evaluation. Immunostaining of p57 showed 3/4 of MCM were focally positive (<5%-20%+), 1/4 of MCM were diffusely positive (70%+), 3/3 of DPM were diffusely positive (≥50%+), 7/9 of HA were diffusely positive (≥50%+), and 2/9 of HA were focally positive (10%+).</p><p><b>CONCLUSIONS</b>Combination of histomorphologic evaluation and p57 immunostaining is insufficient for a definitive diagnosis of PHM. STR genotyping offers an accurate diagnosis of PHM.</p>